COMPLICATIONS
OF FRACTURE
A major objective in the
management of fractures and dislocations is to avoid as many complications as
possible. The principles of fracture treatment direct the surgeon to reduce the
fracture and immobilize it with a cast/splint or internal/external fixation
devices, to allow natural healing to occur. A variety of complications, either
as a consequence of the injury itself or as a consequence of treatment, can
produce serious and permanent problems. Acute complications such as damage to
nerves and blood vessels, adult respiratory distress syndrome, and infection
usually arise from the injury itself. Complications also develop during the
healing process and may lead to irreparable loss of function. Chronic
complications include failure of union, deformities, osteoarthritis, joint
stiffness, implant failure, and reflex sympathetic dystrophy.
Neurovascular Injury
Displacement of fracture
fragments or bone ends at a dislocated joint often produces compression or
laceration of adjacent vessels and nerves. Critical neurovascular structures
(e.g., the brachial plexus) lie deep in the limb, close to the skeleton, which
protects them from injuries. A fracture or dislocation makes nerves or vessels
vulnerable to injury from sharp bone fragments or from entrapment in the
fracture site.
Neurovascular complications
must be identified by careful examination immediately after the injury and
after any manipulation of the injured limb. Some complications are not
immediately evident but do appear 24 to 48 hours after injury. Reexamination
and monitoring are essential both during this period and while circumferential
compression dressings and casts are in place. Prompt and sometimes aggressive
treatment is required to restore function and prevent permanent loss.
Radial Nerve Palsy
The radial nerve is commonly
damaged in fractures of the shaft of the humerus (see Plates 2-19 and 2-32).
Normally protected in the spiral groove on the humeral shaft, the nerve is
easily impaled by a fracture fragment or entrapped in the fracture site.
Aggressive manipulation of the fracture during closed reduction may also result
in nerve entrapment. Wristdrop is a common long-term consequence of this
injury.
Neurovascular Injury to
Elbow
A musculoskeletal injury that
is frequently associated with neurovascular injury is the supracondylar
fracture of the humerus in children. In the most common extension-type
fracture, the humeral shaft fragment is displaced anteriorly, impinging on the
critical neurovascular structures in front of the elbow. The median, radial,
and ulnar nerves are all susceptible to direct injury from the displaced
fracture fragment (median nerve most commonly injured), and the brachial artery
may be lacerated or entrapped in the fracture site at the time of injury or
during closed reduction. Distal neurovascular function must be assessed
critically, and manipulative reduction must be very careful and gentle.
Joint Stiffness
Effective immobilization of a
fracture or dislocation in a cast or splint, if prolonged, can lead to joint
stiffness, which may prove to be a bigger problem than the injury itself.
Immobilization lasting more than a few weeks leads to scarring of the joint
capsule and contracture of the muscles, and it also impairs the nutrition of
the articular surfaces. With prolonged immobilization, adhesions develop across
the articular surfaces, even in joints that had not been injured directly. In
addition, prolonged immobilization results in marked atrophy of the muscles in
and around the site of injury. Rehabilitation to regain motion can be a long
and difficult process that may not restore full function.
Most treatment protocols,
either nonoperative or operative, typically recommend beginning range of motion
early in the recovery period to avoid the development of stiffness.
Nonoperatively, this can be accom- plished with use of functional braces that
adequately immobilize the injury for healing but still allow range of motion.
For example, traditional cast immobilization for a fracture of the humeral
shaft requires immobilization of the shoulder and elbow joints in a shoulder
spica cast. Such immobilization of both joints for 8 to 10 weeks would lead to
a significant loss of function. Conversely, a functional brace allows active
range of motion in the shoulder and elbow joints yet provides adequate support
of the healing fracture. A functional brace is applied 10 to 14 days after
injury, once the initial swelling has subsided. The brace is adjustable and can
be tightened to provide firm support about the arm and maintain acceptable
alignment of the fracture. Inability to maintain stable reduction of a fracture
or dislocation early in the postinjury period through non-operative measures is
an indication for open reduction and internal fixation. Surgical stabilization
will then allow range-of-motion exercises without fear of loss of reduction.
When joint stiffness develops,
restoring motion often requires a long-term rehabilitation program. After the
patient regains joint motion with gentle passive range-of-motion exercises,
active exercises are begun to strengthen the atrophied muscles. When fixed
contractures fail to respond to aggressive and prolonged rehabilitation,
surgical release of soft tissue may be necessary as a last resort. At the elbow
joint, this includes release or excision of the contracted and thickened joint capsule.
